An updated retelling of the classic Richard Wagner opera, Der Ring Des Nibelungen, Harlock Saga unveils one of Captain Harlock's adventures regarding how he first meets the young Tadashi Daiba and revisits his relationships with some old friends.

The adventure reunites Harlock and his best friend and trusted engineer Tochiro Oyama with their old companions Emeraldas (from Queen Emeraldas), Meeme, and Maetel (from Galaxy Express 999). Set to music taken from and inspired by Wagner's masterpiece, Harlock Saga takes them to such far off places as the beautiful Planet Rhein, and Valhalla- the so called "Planet of the Gods" located at the center of the universe. Harlock and the crew of the Arcadia must recover the Rhein Gold which is a very precious and very powerful metal that controls the flow of time in the universe. The Rhein Gold has been stolen by a sinister bandit who's not at all what he seems and seeks to bring darkness to all the galaxy with the ring made from Rhein Gold. Can Harlock and his crew prevent the imminent doom that faces the universe? The adventure is about to unfoldâ€¦